The history of climate science goes back to the early 1900's. This section contains a chronological listing of relevant climate science discoveries and events related to anthropogenic global warming. The information here was compiled by Spencer Weart (see links for reference).

How do we know current global warming is human caused, or man made? Is global warming real, or a hoax? Consider the facts: the climate system is indicated to have left the natural cycle path; multiple lines of evidence and studies from different fields all point to the human fingerprint on current climate change; the convergence of these evidence lines include ice mass loss, pattern changes, ocean acidification, plant and species migration, isotopic signature of CO2, changes in atmospheric composition, and many others. The only identifiable cause explaining these changes with confidence is human influence and increased greenhouse gas emissions. Science has simply not found any other cause factor that can account for the scale of the recent increase in radiative forcing and associated warming.

Most understand the Keeling curve as an upward trend of CO2 in the atmosphere as measured by the Mauna Loa measurements of Charles David Keeling. But there are two Keeling curves and they are related to each other in more than one way. While CO2 increases, it stands to reason that O2 will decrease (C + O2 = CO2). The two curves also have family ties.

Global warming is not only expected to cause a latitudinal shift of the jet-stream, it already has. There has been a measured poleward of the jet-stream in the past 30 years. This is an expected result of global warming.

What are Milankovitch Cycles? Natural global warming, and cooling, is considered to be initiated by Milankovitch cycles. These orbital and axial variations influence the initiation of climate change in long-term natural cycles of 'ice ages' and 'warm periods' known as 'glacial' and 'interglacial' periods. Our current climate forcing shows we are outside of that natural cycle forcing range.

Natural variation includes internal and external variability influences such as the solar Schwabe cycle, oceanic cycles, seasonal influences based on changes caused by the interaction of the various natural oscillations in the climate system. These variations combined influence regional climate and weather on periodic basis as well as influence weather event patterns.

The North Atlantic Oscillation (NAO) is a measure of the strength of the westerlies across the North Atlantic. Originally defined by Sir Gilbert Walker in 1932 as the difference in pressure between Ponta Delgada on the Azores and Stykkisholmur in Iceland.